Flyback-Based Three-Port Topologies for  Electrolytic Capacitor-Less LED Drivers

 

Abstract

Electrolytic capacitors are the components   that mainly impact the lifetime of AC/DC light-emitting  diode (LED) drivers. Therefore, eliminating electrolytic  capacitors from LED drivers is of vital importance. Firstly,  the basic derivation concept of a family of Flyback-based  three-port converters (TPC) for electrolytic capacitor-less  LED drivers is addressed in this paper, by manipulating the  power flow a input port, output port, and storage  capacitors. Together with the derivation of existing  topologies, new topologies are also proposed. After  evaluation, an integrated dual Flyback converter (IDFC) is  chosen, which requires less switching components and  simpler control strategy. Following that, the operation  principle and switching modes of the IDFC are elaborated,  as well as the parameter design and implementation of  control strategy. Finally, experiments on a laboratory  prototype are carried out to verify the feasibility of the  proposed topology.   

EXISTING  SYSTEM: 

The core idea of eliminating electrolytic capacitors through  control strategy improvement is to reduce the pulsating power  ΔE, where the required capacitance will consequently be  reduced. Certain amount of harmonics is injected into the input  current to lower the ripple magnitude of input power and to  decrease the peak-to-average power ratio (PAPR) in, as  shown in. But smaller capacitance requires higher  injected harmonic current magnitude, resulting in lower PF  . Another solution of allowing LED to endure reasonable  pulsating current is brought up in , to make the output  power pulsate at the same frequency with the input power, in  which case the pulsating power that the capacitor needs to deal  with will be reduced, like Fig. 1 (b). Low-frequency current  driving will sabotage the input PF and the general performances  of LED however. A method offered in is capable of  manipulating the output power by splitting the load into several  modules and conducting phase shifted operation of modules,  depicted in which is deeply dependent on the number  of modules the LED load can be split to and is better suitable  for high-power applications.

 

 

PROPOSED  SYSTEM: 

If the pulsating power ΔE remains unchanged, the average  voltage or ripple magnitude on storage capacitor can be  increased by restructuring the topology, and the capacitance  needed is reduced in turn. A proposal of power decoupling  through paralleling a bi-directional converter between PFC  converter and LED load to balance ΔE is put forward. DC/DC converter is used to compensate the output  voltage ripple in PFC converter, weakening its  influences on LED,. Nevertheless,  topologies mentioned are loosely integrated  and add to the difficulty in control strategy. 

CONCLUSION

The problem of eliminating electrolytic capacitor is one of   the barriers blocking the development of LED lighting drivers.  The paper demonstrates the deduction principle of TPC  topologies and proposes a series of topologies of electrolytic  capacitor-less TPC LED driver based on the Flyback converter.   An integrated dual Flyback converter (IDFC) is selected for  further investigation, which requires less switching  components and simpler control strategy. The operation  principle and switching modes of the proposed IDFC are  elaborated, as well as the parameter design. Although  experiments have proved the feasibility of the proposed  topology, it needs to be further explored for better performance.

REFERENCES   

[1] R. Haitz, “Another semiconductor revolution: this time it’s lighting,” in  Proc. Advances in solid state physics, 2003, pp. 35–50.

[2] R. Haitz, and J. Y. Tsao, “Solid-state lighting:‘The case’10 years  after and future prospects,” physica status solidi, vol. 208,  no. 1, pp. 17–  29, Jan.2011.

[3] A. Lay-Ekuakille, F. Aniello, F. Miduri, D. Leonardi, and A. Trotta,  “Smart control of road-based LED fixtures for energy saving,” in Proc.  IEEE Intell. Data Acquisition Adv. Comput. Syst., 2009, pp. 59–62.

[4] X. Tao, and S. R. Hui, “Dynamic photoelectrothermal theory for  light-emitting diode systems,” IEEE Trans. on Ind. Electron., vol. 59,  no.  4, pp. 1751–1759, Apr.2012.

[5] S. Hui, and Y. Qin, “A general photo-electro-thermal theory for light  emitting diode (LED) systems,” IEEE Trans. on Power Electron., vol. 24,  no. 8, pp. 1967–1976, Aug.2009.

[6] M. Dyble, N. Narendran, A. Bierman, and T. Klein, “Impact of dimming  white LEDs: chromaticity shifts due to different dimming methods,” in  Proc. Fifth International Conference on Solid State Lighting., pp. 291–  299, Jul.2005.

[7] ENERGY STAR® Program Requirements Product Specification for  Luminaires,Washington, D.C.:U.S. Environmental Protection Agency  and U.S. Department of Energy, 2007.

[8] IEC  -1000-3-2 Class C. Harmonics standards for commercial electronic  products.

[9] Philips. LED Lifetime.2013.  [Online]. Available: http://wwww. Colorki   netics.com/support/White papers/LED Lifetime. Pdf

[10] L. Han, and N. Narendran, “An accelerated test method for predicting the  useful life of an LED driver,” IEEE Trans. on Ind. Electron., vol. 26, no.  8, pp. 2249–2257, Aug.2011.

Flyback-Based Three-Port Topologies for  Electrolytic Capacitor-Less LED Drivers

 

Abstract

Electrolytic capacitors are the components   that mainly impact the lifetime of AC/DC light-emitting  diode (LED) drivers. Therefore, eliminating electrolytic  capacitors from LED drivers is of vital importance. Firstly,  the basic derivation concept of a family of Flyback-based  three-port converters (TPC) for electrolytic capacitor-less  LED drivers is addressed in this paper, by manipulating the  power flow a input port, output port, and storage  capacitors. Together with the derivation of existing  topologies, new topologies are also proposed. After  evaluation, an integrated dual Flyback converter (IDFC) is  chosen, which requires less switching components and  simpler control strategy. Following that, the operation  principle and switching modes of the IDFC are elaborated,  as well as the parameter design and implementation of  control strategy. Finally, experiments on a laboratory  prototype are carried out to verify the feasibility of the  proposed topology.   

EXISTING  SYSTEM: 

The core idea of eliminating electrolytic capacitors through  control strategy improvement is to reduce the pulsating power  ΔE, where the required capacitance will consequently be  reduced. Certain amount of harmonics is injected into the input  current to lower the ripple magnitude of input power and to  decrease the peak-to-average power ratio (PAPR) in, as  shown in. But smaller capacitance requires higher  injected harmonic current magnitude, resulting in lower PF  . Another solution of allowing LED to endure reasonable  pulsating current is brought up in , to make the output  power pulsate at the same frequency with the input power, in  which case the pulsating power that the capacitor needs to deal  with will be reduced, like Fig. 1 (b). Low-frequency current  driving will sabotage the input PF and the general performances  of LED however. A method offered in is capable of  manipulating the output power by splitting the load into several  modules and conducting phase shifted operation of modules,  depicted in which is deeply dependent on the number  of modules the LED load can be split to and is better suitable  for high-power applications.

 

 

PROPOSED  SYSTEM: 

If the pulsating power ΔE remains unchanged, the average  voltage or ripple magnitude on storage capacitor can be  increased by restructuring the topology, and the capacitance  needed is reduced in turn. A proposal of power decoupling  through paralleling a bi-directional converter between PFC  converter and LED load to balance ΔE is put forward. DC/DC converter is used to compensate the output  voltage ripple in PFC converter, weakening its  influences on LED,. Nevertheless,  topologies mentioned are loosely integrated  and add to the difficulty in control strategy. 

CONCLUSION

The problem of eliminating electrolytic capacitor is one of   the barriers blocking the development of LED lighting drivers.  The paper demonstrates the deduction principle of TPC  topologies and proposes a series of topologies of electrolytic  capacitor-less TPC LED driver based on the Flyback converter.   An integrated dual Flyback converter (IDFC) is selected for  further investigation, which requires less switching  components and simpler control strategy. The operation  principle and switching modes of the proposed IDFC are  elaborated, as well as the parameter design. Although  experiments have proved the feasibility of the proposed  topology, it needs to be further explored for better performance.

REFERENCES   

[1] R. Haitz, “Another semiconductor revolution: this time it’s lighting,” in  Proc. Advances in solid state physics, 2003, pp. 35–50.

[2] R. Haitz, and J. Y. Tsao, “Solid-state lighting:‘The case’10 years  after and future prospects,” physica status solidi, vol. 208,  no. 1, pp. 17–  29, Jan.2011.

[3] A. Lay-Ekuakille, F. Aniello, F. Miduri, D. Leonardi, and A. Trotta,  “Smart control of road-based LED fixtures for energy saving,” in Proc.  IEEE Intell. Data Acquisition Adv. Comput. Syst., 2009, pp. 59–62.

[4] X. Tao, and S. R. Hui, “Dynamic photoelectrothermal theory for  light-emitting diode systems,” IEEE Trans. on Ind. Electron., vol. 59,  no.  4, pp. 1751–1759, Apr.2012.

[5] S. Hui, and Y. Qin, “A general photo-electro-thermal theory for light  emitting diode (LED) systems,” IEEE Trans. on Power Electron., vol. 24,  no. 8, pp. 1967–1976, Aug.2009.

[6] M. Dyble, N. Narendran, A. Bierman, and T. Klein, “Impact of dimming  white LEDs: chromaticity shifts due to different dimming methods,” in  Proc. Fifth International Conference on Solid State Lighting., pp. 291–  299, Jul.2005.

[7] ENERGY STAR® Program Requirements Product Specification for  Luminaires,Washington, D.C.:U.S. Environmental Protection Agency  and U.S. Department of Energy, 2007.

[8] IEC  -1000-3-2 Class C. Harmonics standards for commercial electronic  products.

[9] Philips. LED Lifetime.2013.  [Online]. Available: http://wwww. Colorki   netics.com/support/White papers/LED Lifetime. Pdf

[10] L. Han, and N. Narendran, “An accelerated test method for predicting the  useful life of an LED driver,” IEEE Trans. on Ind. Electron., vol. 26, no.  8, pp. 2249–2257, Aug.2011.